Skip to Content Go to sign in Skip to Primary Navigation Skip to Secondary Navigation Skip to Page Navigation Skip to Header Navigation Skip to Footer Navigation Read more about accessability options and our navigation

Physics Classroom is making strides to make our site accessible to everyone. Our site contains 6 navigation areas. The Primary, Secondary, and Page Level navigations have a screen reader version of their nav structure that allows using the left and right keys to navigate sibling navigation items, and up or down keys to navigate parent or child navigation items. The others can be navigated using tabs. The Primary Navigation handles the first 2 levels of site pages. The Secondary (which is not always available) handles the 3rd and 4th level of structure. The Page level navigation allows you to navigate the current page's headings quickly. The Header Navigation contains the Light/Dark Mode toggle, Search, Notifications and account login. The Breadcrumb Navigation contains the breadcrumb of the current page. If the current page has a breadcrumb, you can get to it by skipping to the content and tabbing in reverse (shift plus tab). The Footer Navigation contains links such as Privacy, Contact, about and terms. Some resources contain an Audio Player that can be activated by holding down the T key for 3 seconds, and then using K to pause and resume. While not every area of Physics Classroom is usable purely from keyboard and screen reader, we are committed to continue work on making this possible. If you have questions or need additional help, please use this link to contact us.

Return to screen reader navigation
Home Minds On Newton's Laws Mission NL1 Inertia and Newton's First Law Help Help 5

Mission NL1 Inertia and Newton's First Law

The Question

Inertia refers to ...

Define Help

Definition of Inertia:
Inertia is the property of an object which describes its natural tendency to keep on doing whatever it is doing.

Don't be Fooled

Many beginning students of Physics have the conception of inertia as some sort of force. To them, inertia is the force that acts upon a moving object to keep it moving and prevent it from slowing down. But don't be fooled! Inertia is simply the tendency of an object to keep on doing whatever it is doing. It is the natural tendency of an object to stubbornly maintain its state of motion. Inertia is not a push or pull on an object. It is the intrinsic property of an object. A push or pull on an object is known as a force. And a force is not needed for an object to maintain its state of motion. In fact a push or pull upon an object (when unbalanced) would alter an object's state of motion and cause it to change its velocity.

Tune In! Listen!

Click the button below to play an audio file in a separate window.




 

Hot Link